Method for producing an alternator assembly housing member

ABSTRACT

An alternator assembly  10  having a pair of housing members  11, 12  which cooperatively contain a stator  24 , rotor  18 , and bearing  29 . The housing member  12  includes an integrally formed bearing sleeve member  40  which receives the bearing  29  and allows the rotor  18  to rotate within the assembly  10.

CROSS REFERENCE TO RELATED DOCUMENT

The present application is a division of application Ser. No.09/470,866, now U.S. Pat. No. 6,278,208 which was filed on Dec. 23rd1999.

FIELD OF THE INVENTION

This invention relates to an alternator assembly and more particularly,to an alternator assembly for use within a vehicle and which includes aselectively movable rotor which is supported by a bearing which isretained in the assembly by use of an integrally formed bearing sleevemember.

BACKGROUND OF THE INVENTION

Alternator assemblies are employed in many devices and/or apparatusesand are generally effective to selectively provide electrical current tomany elements and/or components which are operatively contained withinthese devices and/or apparatuses.

Particularly, alternator assemblies typically include a selectivelymovable rotor which is movably contained or deployed within a housing.The housing typically includes and/or employs a stator which cooperateswith the selectively movable rotor to provide electrical current andenergy. While these alternator assemblies do provide electrical energy,they suffer from some drawbacks.

For example and without limitation, the housing of many alternatorassemblies is typically formed from aluminum material and the rotor istypically formed from commercially available and conventional steelmaterial. A “rear” steel bearing assembly having a first portion whichis typically “press fit” into the “rear” or “back” alternator assemblyhousing and a second portion which is “press fit” onto the rotor shaftis usually employed to operatively support the rotor in the “rear” or“back” alternator assembly housing.

Since the thermal coefficient of expansion of aluminum is much greaterthan that of steel, a gap is typically formed between the first portionof the steel bearing assembly and the alternator housing which causesthe contained rotor shaft to be unsecured or loosely secured within therear or back alternator housing, thereby undesirably decreasing theoverall performance of the alternator.

To address the previously delineated drawback, a material such asplastic or thermoplastic is typically formed into a cup and is placedover the first portion of the steel bearing assembly and is “fit” (e.g.,press fit, transitionally fit, or slip fit) into the rear alternatorassembly housing. The plastic material has a coefficient of expansionwhich is relatively larger than the aluminum material of the rearalternator assembly housing and selectively expands in order to “fillthe gap” which is formed between the first portion of the steel bearingassembly and the alternator assembly housing. Alternatively, grooves areformed or “cut” into the first portion of the bearing assembly and theplastic material is selectively molded into these selectively formedgrooves to form what is often referred to as “expansion coefficientbands”. While the applied plastic material does provide for a moresecure fit of the rotor shaft into the rear alternator assembly housing,the technique also suffers from several drawbacks.

For example and without limitation, the use of such a plastic cup orsleeve undesirably increases overall production cost and complexity. Theuse of selectively formed grooves also undesirably increases overallproduction costs. Further, the utilized plastic materials are relativelyefficient insulators and undesirably prevent heat from being easily andefficiently dissipated from the bearing assembly, thereby undesirablydecreasing the operating life of the bearing assembly and the alternatorassembly. Further, the applied plastic material “creeps” and/or movesover time, thereby causing undesirable mis-alignment between the rotorand the stator.

To overcome these drawbacks, one attempt has been made to create andoperatively use a steel cup which is selectively placed over the bearingassembly and which is selectively attached or fastened into thealternator assembly. While this steel cup overcomes the previouslydelineated “creep” and heat dissipation drawbacks, it requires severalfasteners which increase the overall production cost and complexity ofthe production or manufacturing processes.

There is therefore a need for a new and improved alternator assemblywhich overcomes some or all of the previously delineated drawbacks ofprior alternator assemblies.

SUMMARY OF THE INVENTION

It is a first object of the present invention to provide an alternatorassembly which overcomes some or all of the previously describeddisadvantages of prior alternator assemblies.

It is a second object of the present invention to provide an alternatorassembly which overcomes some or all of the previously describeddisadvantages of prior alternator assemblies and which, by way ofexample and without limitation, includes a steel bearing sleeve which isintegrally formed within the alternator assembly housing and whichoperatively supports and receives a rotor bearing member, effective toallow the rotor to move within the housing and to allow the alternatorassembly to provide electrical energy.

According to a first aspect of the present invention an alternatorassembly is provided. The alternator assembly includes a rotor; and ahousing which includes an integrally formed bearing sleeve member.

According to a second aspect of the present invention a method formaking an alternator assembly housing is provided. The method includesthe steps of providing a die; providing a sleeve member; placing thesleeve member into the die; creating the housing by use of the die,thereby producing an alternator assembly housing having an integrallyformed sleeve member.

These and other aspects, features, and advantages of the presentinvention will become apparent by reading the following detaileddescription of the preferred embodiment of the invention, including thesubjoined claims, and by reference to the following drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective and unassembled view of an alternator assemblywhich is made in accordance with the teachings of the preferredembodiment of the invention;

FIG. 2 is a side sectional view of the “rear” alternator assemblyhousing which is shown in FIG. 1; and

FIG. 3 is a perspective view of a die assembly which is used to make therear alternator assembly housing which is shown in FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

Referring now to FIG. 1, there is shown an alternator assembly 10 whichis made in accordance with the teachings of the preferred embodiment ofthe invention. It should be appreciated that although one type ofvehicle alternator assembly 10 is shown in FIG. 1, other types ofalternator assemblies may utilize the integrally formed bearing sleeveassembly of the present invention and that the present invention is notto be limited by any particular type of vehicle alternator assemblyincluding the type of vehicle alternator assembly which is depictedwithin FIG. 1.

As shown, alternator assembly (“assembly”) 10 includes a first generallyround or “front” housing member 11 and a second or “rear” housing member12 which each have a pair respective and cooperating rotor receptionorifices 13, 16. Assembly 10 further includes a typical rotor 18 havingseveral magnetic pole pieces or members 20 disposed upon a shaft 22, astator member 24, a rectifier member 26, a belt driver or pulley 27, abearing 29, a regulator 15, and a cover or cap portion or member 17.

Particularly, portion 28 of the shaft 22 is adapted to be receivedwithin and to traverse the bearing 29 and to be received within therotor reception orifice 16. The rectifier 26, regulator 15, and rearhousing 12 are operatively contained between the cap portion or member17 and the rear housing 12. Portion 30 is adapted to be received withinand to traverse the stator member 24 and the rotor reception orifice 11of the front housing member or portion 13 before being received into thepulley or drive member 27. In this manner, the drive member 27, which ismoved by a portion of the vehicle engine (not shown) selectively causesthe rotor 18 to move, thereby producing electrical current and energy.

According to the teachings of the preferred embodiment of the invention,the rear or back alternator assembly housing member 12 includes anintegrally formed bearing sleeve member 40 which is adapted to receiveand to operatively contain the bearing 29. Particularly, integrallyformed bearing sleeve member 40 is generally round and generallyconforms to the size and the shape of and is positioned within the rotorreception orifice 16. Further, in one non-limiting embodiment, member 40includes several skive portions 42 which outwardly project from themember 40 and into the housing 12, thereby further securing the member40 within the housing 12. In a further non-limiting embodiment of theinvention, member 40 is manufactured from commercially available andconventional steel material, thereby allowing heat to be readilydissipated from the rotor portion 28. The bearing sleeve member 40 isintegrally formed within the member 12, thereby obviating the need forfasteners or other devices or members to separately attach member 40 tomember 12 and thereby simplifying the overall assembly and production ofthe alternator assembly 10. The integral placement of the member 40within the rear housing member 12 is shown best in FIG. 3.

That is, as shown in FIG. 3, a typical casting die 50 is used to producethe rear housing member 12. Particularly, die 50 has a certain contouredcavity 52 which has a shape which corresponds to the overall shape andsize of the member 12. Prior to casting, bearing sleeve member 40 isplaced within the die and, more particularly, is placed within theportion of the cavity 52 corresponding to the rotor reception orifice16. The member or housing 12 is cast while the bearing sleeve 40 resideswithin the cavity 52, thereby producing a rear alternator housing member12 having an integrally formed bearing sleeve member 40 which resideswithin the rotor reception orifice 16 in the manner which has beenpreviously delineated.

It should be realized that the invention is not limited to the exactmethod, construction, or embodiment which has been previouslydelineated, but that various changes and modifications may be madewithout departing from the spirit and the scope of the invention as ismore fully set forth in the following claims.

What is claimed is:
 1. A method for producing an alternator assemblyhousing member which selectively receives a bearing having an outerrace, said method comprising the steps of: providing a die; causing saiddie to include a first surface in the form of said housing member;placing a bearing sleeve member upon said die surface, wherein saidbearing sleeve member is shaped to receive said outer race of saidbearing and has a plurality of skive portions which outwardly projectfrom said bearing sleeve member; and using said die to create saidhousing member, wherein said outwardly projecting skive portions projectinto said housing member, thereby forming said bearing sleeve memberwithin said housing member.
 2. The method of claim 1 wherein saidhousing includes a rotor reception portion and wherein said bearingsleeve member is formed within said rotor reception portion.
 3. Themethod of claim 2 wherein said bearing sleeve member is formed fromsteel.
 4. The method of claim 3 wherein said housing member is cast fromaluminum.
 5. The method of claim 1 wherein said bearing sleeve member isadapted to operatively contain a bearing.
 6. A method for casting ahousing member for an alternator assembly having a bearing with an outerrace, said method comprising the steps of: providing a die having acontoured cavity corresponding to a shape of said housing member, andincluding a portion corresponding to a rotor reception orifice;providing a bearing sleeve member which is shaped to receive said outerrace of said bearing and has a plurality of skive portions whichoutwardly project from said bearing sleeve member; placing said bearingsleeve member within said portion of said cavity corresponding to saidrotor reception orifice; and casting said housing member while saidbearing sleeve member resides within said portion of said cavitycorresponding to said rotor reception orifice, wherein said outwardlyprojecting skive portions project into said housing member, therebyintegrally forming said bearing sleeve member within said housingmember.
 7. The method of claim 6 wherein said bearing sleeve member ismanufactured from steel.
 8. The method of claim 6 wherein said bearingsleeve member is adapted to operatively contain a bearing.
 9. The methodof claim 6 wherein said housing member is cast from aluminum.